It was one of the highlights of the year for cinema-goers across the globe - the moment the sixth Harry Potter film hit the screens.

And as Harry Potter And The Half Blood Prince premiered at special midnight screenings in the US on Wednesday night eager fans helped the film generate over $20 million in ticket sales.

Figures from the UK box office are to be released later this week, but, if Daniel Radcliffe, Emma Watson and Rupert Grint's raptuous welcome at the London premiere is anything to go by, takings are likely to be just as impressive.

The film has overtaken previous record-holder The Dark Knight, which took $18.5 million at midnight showings last summer. It has also made $10m more than the previous wizard adventure did on its opening night.